ML24059A404
| ML24059A404 | |
| Person / Time | |
|---|---|
| Site: | Prairie Island  |
| Issue date: | 03/06/2024 |
| From: | Northern States Power Co, Xcel Energy |
| To: | Ballard B NRC/NRR/DORL/LPL3 |
| Kuntz R | |
| References | |
| EPID L-2024-LRM-0034 | |
| Download: ML24059A404 (1) | |
Text
Prairie Island License Amendment Request to Modify Technical Specifications Definitions and Approve Plant-Specific Methods for Response Time Testing 03.06.2024
Agenda
- Purpose
- Background
- Proposed Licensing Action
- Technical Specifications Changes
- Site-specific Methodology
- Schedule
- Closing Remarks 2
The purpose of this meeting is to discuss proposed License Amendment for Prairie Island Nuclear Generating Plant (PINGP)
Units 1 and 2 to:
Revise the Technical Specifications (TS) definition of REACTOR TRIP SYSTEM (RTS) RESPONSE TIME by implementing a plant-specific methodology for allocating response times.
This includes a request to approve a proposed plant-specific methodology for allocating response times.
Revise TS Table 3.3.1-1 to apply TS Surveillance Requirement 3.3.1.16 Response Time Testing to those RTS functions that have an assumed time delay in the accident analyses.
Purpose 3
TSTF-569 permits licensees, in lieu of measurement, to verify the Reactor Trip System (RTS) response times of certain component types by using the methodology contained in TSTF-569 and WCAP-14036.
NSPM evaluated adopting TSTF-569 to more efficiently use Instrument & Control maintenance staff during refueling outages.
NSPM determined that TSTF-569 does not apply to the PINGP Process Protection System (PPS) portion of the RTS. The PINGP PPS was not among those listed in WCAP-14036 and associated NRC Safety Evaluation.
Thus, a plant-specific method (like the one approved with TSTF-569) for allocating response times will be proposed with the LAR.
Background
4
NSPM will propose a method like that of TSTF-569, Revision 2, for allocating response times to PINGP RTS.
The scope of the LAR will vary from the TSTF:
PINGP TS do not include a definition of ESFAS Response Time.
PINGP TS specifically exclude sensors from the scope of RTT.
Proposed Licensing Action Technical Specifications Changes 5
The definition of RTS Response Time will be revised.
Table 3.3.1-1 will be revised to apply SR 3.3.1.16, Response Time Testing, to only those RTS Functions with assumptions of time delays in the accident analyses.
SR 3.3.1.16 will be added to the SR requirements of four functions SR 3.3.1.16 will be removed from the SR requirements of two functions Proposed Licensing Action Technical Specifications Changes (continued) 6
SR 3.3.1.16 will be added to the SR requirements of four functions:
8.a. Pressurizer Pressure - Low 8.b. Pressurizer Pressure - High
- 10. Reactor Coolant Flow - Low
3.b. Power Range Neutron Flux Rate - High Negative Rate
- 5. Source Range Neutron Flux Proposed Licensing Action Technical Specifications Changes (continued) 7
Proposed Licensing Action Technical Specifications Changes (continued) 8 NSPM Proposed mark up
Proposed Licensing Action Technical Specifications Changes (continued) 9 NSPM Proposed mark up
Proposed Licensing Action Technical Specifications Changes (continued) 10 NSPM Proposed mark up
Proposed Licensing Action Technical Specifications Changes (continued) 11 NSPM Proposed mark up
Bases for removing SR 3.3.1.16 from Function 3b:
Function 3b (negative rate trip) is discussed in the dropped rod analysis, but that analysis assumes no reactor trip; therefore no assumptions about time delays.
Proposed Licensing Action Technical Specifications Changes (continued) 12
Bases for removing SR 3.3.1.16 from Function 5:
Function 5 (source range trip) is not credited in the rod withdrawal from subcritical (RWFS) analysis and no time delay assumption is included in the accident analysis for the source range trip.
Proposed Licensing Action Technical Specifications Changes (continued) 13
NSPM has developed and will submit for approval with the LAR a site-specific methodology for allocating response times to the PINGP RTS components that are subject to Response Time Testing.
The proposed methodology will be modeled on TSTF-569, Revision 2, Attachment 1, Methodology 2 (hereafter Methodology 2) but will account for the specific PPS components installed in PINGP Units 1 and 2.
Proposed Licensing Action Site-Specific Methodology 14
Nuclear Instrumentation System (NIS) and Relay Reactor Protection System (RRPS): Methodology 2 applies directly to PINGP.
The bounding response times for NIS and RRPS as shown in WCAP-14036-P-A will be evaluated in accordance with the NRC-approved methodology as discussed in TSTF-569,.
Proposed Licensing Action Site-Specific Methodology (continued) 15
PPS: Foxboro H-Line/Curtiss-Wright Scientech NUS and the Hagan 7100 Line (previously approved) of equipment are similar NSPM proposes to use Methodology 2 Analyze the system modules for contribution to protection function Perform failure modes and effects analysis (FMEA) on modules that perform protection function Determine bounding response times for components Evaluate impact of components on system response time Compare FMEA bounding time delay to USAR assumed time delay Proposed Licensing Action Site-Specific Methodology (continued) 16
Proposed Licensing Action Site-Specific Methodology (continued) 17 LAR will propose to remove SR 3.3.1.16 for functions 3.b and 5 LAR will propose to add SR 3.3.1.16 for functions 8.a, 8.b, 10 and 13
NSPM plans to submit the LAR and Methodology by April 10, 2024, and request NRC approval 12 months from acceptance with a goal of implementation with the 2025 Unit 2 refueling outage.
Schedule 18